Industrial network system

ABSTRACT

A central communication unit  110  and a terminal communication unit  120  are provided with a priority order number storing unit  115  and fifo type storing units, and perform communication according to the priority order of data communication stored in the priority order number storing unit  115.  At this time the priority order and the layout of respective devices of control objects are optimized and set through a software processing in a host computer according to the communication cycle and response performance required for the devices of control objects, thereby, the plurality of devices of control objects requiring different communication cycles and response performances can be connected on one network.

CLAIM OF PRIORITY

The present application claims priority from Japanese application serialNo. 2010-028869, filed on Feb. 12, 2010, the contents of which is herebyincorporated by references into this application.

FIELD OF THE INVENTION

The present invention relates to an industrial network system thatcontrols a plurality of control objects, and, in particular, relates toan improvement in an industrial network system that multiplexes aplurality of input and output data signals in to a single transmissionpath and achieves wiring saving.

DESCRIPTION OF PRIOR ART

An industrial network system is constituted by a host computer, acentral communication unit connected to the host computer and aplurality of terminal communication units provided with variety types ofI/O ports, and is used by constituting a network through connection thecentral communication unit and the plurality of terminal communicationunits in a form of such as a multi drop and a dizzy chain.

Conventionally, data input and output between a plurality of devicesrepresenting control objects laid out distributedly and a host computerwas performed by directly connecting the respective devices to the hostcomputer, thereby, many wirings were required.

In an industrial network system, when a plurality of devices of controlobjects laid out distributedly are connected to a host computer througha network, and the input and output signals for the devices of controlobjects are multiplexed, the data input and output between the hostcomputer and the plurality of devices of control objects are realizedthrough simple connections with limited wirings, accordingly, suchindustrial network system is primarily utilized in a field ofautomobiles, machine tools and industrial machines like chip mounterswhere such as many numbers and types of devices of control objects arerequired and the layout of the devices is easily distributed.

Further, in an industrial network system, such as required communicationcycle and response performance are greatly different depending ondevices of control objects such as digital I/O devices and servoactuators.

In a conventional industrial network system, in order to guarantee samecommunication cycle and response performance for all of the devicesdepending on the number of devices of control objects connected to onenetwork, it is necessary to constitutes a network that guarantees thatall of the devices operate at their highest required performance, evenwhen required performances of the respective devices of control objectsare different, resultantly, an excessively high communication speed isrequired for the entire network. Such excessively high communicationspeed causes to reduce noise resistance performance of the network, andresults in further shortening of data transmission distance.

In order to resolve such problems, a control method is used in whichdevices requiring high communication cycle and response performance aredirectly connected to a host computer through a separate control linenot via a network. However, this method requires such as extending aplurality of wirings from the host computer and necessitating the hostcomputer performing a different control processing from the side of thenetwork, thereby, the entire system complexes.

Further, a technology is known in which by setting priority and samplinginterval for communication data, information is efficiently collectedfor control devices having a fast communication cycle and a largecommunication traffic (JP-A-2001-19707). However, with this method,since a central communication unit regulates timing by polling, it isnot easy that the central communication unit and terminal communicationunits communicate at free timing. Further, it is difficult to set suchas priority and sampling interval while including a layout of thenetwork.

SUMMARY OF THE INVENTION

The present invention has been made in view of the above referred totasks of the conventional system, and a primary object of the presentinvention is to realize a system that permits to connect on one networka plurality of devices of control objects requiring such as differentcommunication cycle and response performance without necessitating anexcessively high communication speed by properly setting priority ordersof data communication with the respective control objects and a layoutof the devices of control objects on the network.

Another object of the present invention is to realize a system thatpermits to easily constitute a network guaranteeing a requiredperformance by optimizing the priority orders of data communication withthe respective control objects and a layout of the devices of controlobjects on the network as explained above according to such as requiredcommunication cycle and response performance for the respective devicesof control objects and by determining the priority orders as well as bypresenting to a user a network connection configuration in advance.

A primary feature of the present invention resides in an industrialnetwork system that is provided with an central communication unitincluding a host computer interface unit, a first I/O data storing unit,a second I/O data storing unit, an identification number storing unit, acommunication cycle data storing unit, at least one communication port,at least two first in first out (fifo) type storing units per onecommunication port and a central communication control unit, and aplurality of terminal communication units each including one upstreamcommunication port, at least two downstream communication ports, atleast two fifo type storing units per one downstream communication port,at least one I/O port, a terminal communication control unit, anidentification number storing unit, a priority order number storing unitand a communication cycle information storing unit, wherein byconnecting the upstream communication ports of the terminalcommunication units to the communication port in the centralcommunication unit or to a downstream communication port of any otherterminal communication unit in the plurality of terminal communicationunits, priority orders of data communication with the respective controlobjects and a layout of the devices of control objects on the networkare designed to be set properly.

In addition to the above features, highly practical systems are proposedby constituting the present invention in the following embodying manner.

An embodiment is characterized, in that the central communication unitsends numbers representing priority orders of data communication fromthe host computer stored in the priority order number storing unit tothe terminal communication units, the concerned terminal communicationunit stores the received priority order number in the priority ordernumber storing unit, when sending output data to the terminalcommunication unit, the central communication unit stores the outputdata in the fifo type storing unit corresponding to the priority ordernumber of the concerned terminal communication unit, the communicationport takes out orderly the output data from fifo type storing unitsaccording to the height of priority order and sends the same, theterminal communication unit forms its own input data packet by combiningthe input value from the I/O port and the priority order numberinformation stored in the priority order number storing unit and outputsthe same to the upstream, the data from the downstream are stored inseparate fifo type storing units corresponding to the priority ordernumber of the input data packet, and the input data packets stored inthe fifo type storing units are orderly sent out according to theirheight of the priority order to the upstream communication port.

Further, the central communication unit sends to terminal communicationunits individual values based on communication cycles required for everycontrol object that is stored in the communication cycle informationstoring unit from the host computer, the terminal communication unitstores the received individual value based on the communication cycle inthe communication cycle information storing unit and transfers theoutput data at a cycle based on the value to the respective terminalcommunication unit, the central communication unit causes to store theinput value of the I/O port received from the terminal communicationunit in the first input data storing unit, and causes to store the valuein the first input data storing unit in the second input data storingunit based on the communication cycle in the communication cycleinformation storing unit, and the host computer is constituted so as toconfirm the values of the I/O ports of the respective terminalcommunication units with reference to the second input data storing unitin the central communication unit.

In order to achieve the other object of the present invention, theconstitution as well as the setting as follows are also the features ofthe present invention, thereby, a system is realized that permits toeasily constitute a network guaranteeing a required performance of whichwill be explained concretely and in detail with reference to anembodying manner to be carried out as explained herein below.

At first, the summed value of the values of communication cycles storedin the communication cycle information storing units in all of theterminal communication units connected to the network is set below themaximum performance of the network.

Secondly, in order to maintain the communication cycles required for therespective control objects, the values of the priority order number isset so that the time variability of the communication cycles of theterminal communication units is confined within a range of one cycle.

Set values of the priority order numbers of the terminal communicationunits and number of terminal communication units to be passed from thecentral communication unit to an objective terminal communication unitare set based on a communication delay time from a control object to thehost computer required for the respective control devices.

Further, the host computer determines communication delay times fromterminal communication units for the respective control objects bymaking use of priority of terminal communication units, number ofcommunication packets of terminal communication units of which priorityis equal to or higher than the priority order set for the concernedterminal communication unit communication time per one communicationpath and the number of terminal communication units to be passed fromthe central communication unit to an objective terminal communicationunit, changes the priority of the respective terminal communicationunits so as to fulfill a communication delay time required for thecontrol object and sets the priority of the terminal communication unit.

Further, the host computer determines communication delay times fromterminal communication units for the respective control objects bymaking use of priority of terminal communication units, number ofcommunication packets of terminal communication units of which priorityis equal to or higher than the priority order set for the concernedterminal communication unit, communication time per one communicationpath and the number of terminal communication units to be passed fromthe central communication unit to an objective terminal communicationunit, changes the layout of the control object so as to fulfill acommunication delay time required for the control object and sets thenumber of terminal communication units to be passed from the centralcommunication unit to an objective terminal communication unit.

Software in the host computer is provided with a function capable ofsetting the communication cycle required for the control object from theinformation input unit.

Further, the software in the host computer is provided with a functioncapable of setting the communication cycles required for all of thecontrol objects, a maximum allowable communication delay time and aconnection configuration (depth) of the terminal communication units onthe network from the information input unit.

The setting function and the display function of the networkconstitution included in the software of the host computer are mountedthrough a GUI (graphical user interface).

Further, as a concrete application example to industrial machines, whenselecting a plurality of control devices constituting a chip mounter asthe devices of control objects for the industrial network system asexplained above, and connecting the plurality of control devicesconstituting the chip mounter to the plurality of terminal communicationunits of the present system, the effect that will be explained below canbe realized in the chip mounter.

EFFECTS OF THE INVENTION

According to the primary aspect of the present invention, an industrialnetwork system can be constituted in which a plurality of devices ofcontrol objects having different communication cycle and responseperformance are connected on one network, and which is controllable witha proper communication speed.

According to the other aspect of the present invention, since a propersetting of priority order of data communication with the control objectsand of layout of the devices of control objects on the network, which isnecessary for connecting a plurality of devices of control objectshaving different communication cycle and response performance on onenetwork and for controlling with a proper communication speed, can beoptimized and determined through software processing of the hostcomputer, an effect can be accomplished that a network guaranteeingrequired performance of the respective devices of control objects can beeasily constructed.

BRIEF DESCRIPTION OF THE ACCOMPANYING DRAWINGS

FIG. 1 is a diagram showing a constitution of a network I/O system of anembodiment according to the present invention.

FIG. 2 is a view for explaining an example of a packet format used forcommunication in a network according to the present invention.

FIG. 3 is a view for explaining a display example on a screen and afunction of an application in an embodiment according to the presentinvention.

FIG. 4 is a flowchart for explaining a concrete processing sequence foroptimization of priority order number and of network connectionconfiguration according to the present invention.

FIG. 5 is a view for explaining a storing method in a priority ordernumber storing unit and a communication cycle information storing unitaccording to the present invention.

FIG. 6 is a view for explaining a display example on a screen and afunction of an application after completion of optimization processingin an embodiment according to the present invention.

DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS

Herein below, an embodying manner of the present invention will beexplained with reference to one embodiment as shown in the drawings.

FIG. 1 is a constitutional diagram of an industrial network systemrelating to one embodiment according to the present invention. Further,in the drawing, an enlarged illustration of a terminal communicationunit 120 correlated by dotted lines shows the details thereof.

The industrial network system in the present embodiment is constitutedby a host computer 100, a central communication unit 110 and a pluralityof terminal communication units 120.

The host computer 100 is provided with a software 101, a display unit102 and an information input unit 103.

The central communication unit 110 is provided with a host computerinterface unit 104, an output data storing unit 112, a first input datastoring unit 113 a, a second input data storing unit 113 b, anidentification number storing unit 114, a priority order number storingunit 115, a communication cycle information storing unit 116, acommunication port 130 and a central communication control unit 111.

The terminal communication unit 120 is provided with an upstreamcommunication port 131, downstream communication ports 132 a, 132 b, anI/O port 141, an identification number storing unit 114, a priorityorder number storing unit 115, a communication cycle information storingunit 116 and a terminal communication control unit 121.

Further, the central communication unit 110 and the terminalcommunication units 120 are respectively provided with a same number offifo type storing units as the number of priority order numbers for theone communication port 130 and for the downstream communication ports132 a, 132 b.

The upstream communication ports 131 in the respective terminalcommunication units 120 are respectively connected either to thecommunication port 130 in the central communication unit 110 or to thedownstream communication port 132 a or the downstream communicationports 132 b in any other terminal communication unit 120 among theterminal communication units 120.

Further, at the ends of I/O ports 141 in the terminal communicationunits 120, different control objects, for example, such as an I/Ocontrolled device and a servo driver are connected for every one of thepluralities of terminal communication units 120.

Now, an operation of the host computer 100 in the present embodimentwill be explained.

The host computer 100 causes to store information of identificationnumber set at the respective terminal communication units 120 in theidentification number storing unit 114 via the host computer interfaceunit 140. Further, the host computer 100 causes to store priority ordernumber information for the respective terminal communication units 120determined according to a preparation method, which will be explainedlater, via the host computer interface unit 140 in the priority ordernumber storing unit 115.

Further, the host computer 100 causes to store communication cycleinformation for setting updating cycle of input and output value of theI/O port 141 in the respective terminal communication units 120 andwhether the updating of the input and output value is performedperiodically or instantly in the communication cycle information storingunit 116 via the host computer interface unit 140.

Further, the host computer 100 causes to store output values of the I/Oport 141 in the respective terminal communication units 120 in theoutput data storing unit 112 of the central communication unit 110 viathe host computer interface unit 140, and confirms input values from theI/O ports 141 in the respective terminal communication units 120 withreference to the values stored in the second input data storing unit 113b of the central communication unit 110.

Now, an operation of the central communication unit 110 according to thepresent embodiment will be explained.

The central communication unit 110 performs data transmission andreception with the host computer 100 via the host computer interfaceunit 140, and data transmission and reception with the respectiveterminal communication units 120 via the communication port 130controlled by the central communication control unit 111.

When the host computer 100 sets identification numbers of the respectiveterminal communication units 120 in the identification number storingunit 114 and priority order numbers of the respective terminalcommunication unit 120 in the priority order number storing unit 115,the central communication control unit 111 outputs priority order numbersetting packets formed by combining the identification number and thepriority order number for every one of the terminal communication units120 to the communication port 130.

Further, when the host computer 100 sets identification numbers of therespective terminal communication units 120 in the identification numberstoring unit 114 and communication cycle information of the respectiveterminal communication units 120 in the communication cycle informationstoring unit 116, the central communication control unit 111 transmitscommunication cycle information setting packets formed by combining theidentification number and the communication cycle information for everyone of the terminal communication units 120 to the respective terminalcommunication units 120 via the communication port 130.

Further, when an output value for an I/O port 141 in a terminalcommunication unit 120 is set in the output data storing unit 112, thecentral communication control unit 111 instantly transmits an outputdata packet formed by combining the identification number and the outputvalue of the terminal communication unit 120 to the terminalcommunication unit 120 via the communication port 130, and during theperiod of no output value change transmits periodically the output datapacket to the terminal communication unit 120 based on the communicationcycle set in the communication cycle information storing unit 116.

When a plurality of output data packets are prepared, the output datapackets are stored in the respective fifo type storing units 117corresponding to the priority order numbers of the terminalcommunication units 120 stored in the priority order number storing unit115, and the communication port 130 takes out the respective output datapackets orderly from the fifo type storing units 117 according to theheight of priority order thereof and transmits the same to thecorresponding terminal communication unit 120.

Further, when an input data packet formed by combining theidentification number of a terminal communication unit 120 and an inputvalue of the I/O port 141 is inputted via the communication port 130,and when the communication cycle information in the communication cycleinformation storing unit 116 corresponding to the identification numberin the input data packet is set at an instant updating mode, the centralcommunication control unit 111 causes to store the input value of thepacket instantly in the second input data storing unit 113 b, and whenthe communication cycle information is set at a periodic updating mode,the central communication control unit 111 causes to store the inputvalue of the packet in the first input data storing unit 113 a, and thefirst input data storing unit 113 a periodically transfers the inputvalue to the second input data storing unit 113 b based on thecommunication cycle stored in the communication cycle informationstoring unit 116.

The communication port 130 transmits respective packets inputted to thecentral communication control unit 111 or the fifo type storing units117 to the upstream communication port 131 of the connected terminalcommunication unit 120, and outputs a packet received from the upstreamcommunication port 131 of the connected terminal communication unit 120to the central communication control unit 111.

Now, an operation of the terminal communication unit 120 according tothe present embodiment will be explained.

Each terminal communication unit 120 performs, by means of the terminalcommunication control unit 121, data transmission and reception with aconnected device via the I/O port 141, data transmission and receptionwith the central communication unit 110 or another terminalcommunication unit 120 via the upstream communication port 131 and datatransmission and reception with another terminal communication unit 120via the downstream communication port 132 a or the downstreamcommunication port 132 b.

When a packet inputted from the upstream communication port 131 is apriority order number setting packet, and the identification numberinformation in the priority order number setting packet coincides withthe identification number stored in its own identification numberstoring unit 114, the terminal communication control unit 121 causes tostore the priority order number in its own priority order number storingunit 115, and when not coincides, the terminal communication controlunit 121 transmits the packet to the downstream communication port 132 aand the downstream communication port 132 b.

Further, when a packet inputted from the upstream communication port 131is a communication cycle information setting packet, and theidentification number information in the communication cycle informationsetting packet coincides with the identification number stored in itsown identification number storing unit 114, the terminal communicationcontrol unit 121 causes to store the communication cycle information inits own communication cycle information storing unit 116, and when notcoincides, the terminal communication control unit 121 transmits thepacket to the downstream communication port 132 a and the downstreamcommunication port 132 b.

Further, when a packet inputted from the upstream communication port 131is an output data packet, and the identification number information inthe output data packet coincides with its own identification number, theterminal communication control unit 121 refers to the communicationcycle information stored in the communication cycle information storingunit 116, and when the communication cycle information is set at aninstant updating mode, the terminal communication control unit 121outputs instantly the output value of the input data packet to the I/Oport 141. When the communication cycle information is set at a periodicupdating mode, the output value of the output data packet is stored inthe output data storing unit 112, and the output data storing unit 112outputs the output value to the I/O port 141 based on the communicationcycle information stored in the communication cycle information storingunit 116.

Further, when a packet inputted from the upstream communication port 131is an output data packet, and the identification number information inthe output data packet does not coincide with its own identificationnumber, the terminal communication control unit 121 transmits the outputdata packet to the downstream communication port 132 a and thedownstream communication port 132 b.

Further, when the input value from the I/O port 141 changes, theterminal communication control unit 121 instantly transmits an inputdata packet formed by combining the input value, its own identificationnumber and its own priority order number in the priority order numberstoring unit 115 to the upstream port 131, and during the period of noinput value change, the input value is periodically transmitted to theupstream port 131 based on the communication cycle set in thecommunication cycle information storing unit 116.

Further, when an input data packet is inputted from the downstreamcommunication port 132 a or the downstream communication port 132 b, theterminal communication control unit 121 causes to store the input datapacket in a fifo type storing unit 117 corresponding to the priorityorder number included in the input data packet, and takes out therespective input data packets orderly from the fifo type storing units117 according to the height of priority order thereof and transmits thesame from the upstream communication port 131 to the centralcommunication unit 110 or another terminal communication unit 120.

FIG. 2 shows a format of a packet used in data communication. The formatof packet is constituted by a data portion 200, a packet type portion201 indicating types of the packet, an identification number portion 202indicating an identification number of the terminal communication unit120 and a priority order number portion 203 indicating a priority ordernumber set for the terminal communication unit 120.

The data portion 200 is provided with input and output data for the I/Oport 141 in the terminal communication unit 120 or such as the priorityorder number and the communication cycle information set for theterminal communication unit 120.

The packet type portion 201 is provided with, for example, such values,when the packet type is an input data packet, “10”, when an output datapacket, “11”, when a priority order number setting packet, “50”, andwhen a communication cycle setting packet, “60”. After referring to thepacket type portion 201, the central communication unit 110 and theterminal communication unit 120 judge the type of the packet and performprocessing for the respective data.

When transmitting a packet from the central communication unit 110 to aterminal communication unit 120, an identification number set for theterminal communication unit 120 representing transmission destination,namely, the identification number of the terminal communication unit oftransmission destination is set in the identification number portion202, and when transmitting a packet from a terminal communication unit120 to the central communication unit 110, its own identification numberset for the terminal communication unit 120, namely, the identificationnumber of the terminal communication unit 120 of transmission origin isset in the identification number portion 202.

Further, when transmitting a packet from the central communication unit110 to a terminal communication unit 120, a priority order number storedin the priority order number storing unit 115 in the centralcommunication unit 110 is provided in the priority order number portion203. Further, when transmitting a packet from a terminal communicationunit 120 to the central communication unit 110, its own priority ordernumber stored in the priority order number storing unit 115 in theterminal communication unit 120 is set in the priority order numberportion 203.

FIG. 3 is an example of display on a screen by an application 300 basedon a GUI (graphic user interface) that is utilized through the hostcomputer 100, when a system user optimizes the priority order number andthe network connection configuration and sets the same by making use ofthe display unit 102 and the information input unit 103.

The application 300 is constituted by a communication performancesetting portion 301, a network connection configuration setting portion302, a network connection configuration displaying portion 303, aprocess displaying portion 304 and an optimization processing startbutton 305.

The communication performance setting portion 301 is constituted by anidentification number setting portion 310, a communication cycle settingportion 311, a communication delay time setting portion 312 and an inputand output data updating mode setting portion 313, and theidentification number setting portion 310 is provided with a function ofsetting an identification number to a terminal communication unit 120,the communication cycle setting portion 311 a function of setting anupdating cycle of input and output value required for a device ofcontrol object connected to the terminal communication unit 120, thecommunication delay time setting portion 312 a function of setting anallowable maximum communication delay time for the device of controlobject connected to the terminal communication unit 120 and the inputand output data updating mode setting portion 313 a function of settingwhether the required input and output value updating mode is periodic orinstant for the device of control object connected to the terminalcommunication unit 120 respectively through operation of a system user.

The network connection configuration setting portion 302 and the networkconnection configuration displaying portion 303 are constituted by acentral communication unit symbol 320, a terminal communication unitsymbol 321 including an upstream communication port symbol 324 anddownstream port symbols 325 a, 325 b and a connecting state symbol 322.

Further, through operation of a system user, the network connectionconfiguration setting portion 302 connects the upstream communicationport symbol 324 of the terminal communication unit symbol 321 and acommunication port symbol 323 of the central communication unit symbol320, or connects the upstream communication port symbol 324 and any oneof the downstream communication port symbol 325 a or 325 b of anotherterminal communication unit symbol 321 with the connection state symbol322, thereby, a network structure is prepared on the software.

The network configuration displaying portion 303 displays a result afterthe network connection configuration set in the network connectionconfiguration setting portion 302 is optimized and modified through aprocessing as will be explained later. Further, the terminalcommunication unit symbol 321 displays the designated identificationnumber therein.

After all of setting of the communication performance setting portion301 and the network connection configuration setting portion 302 hasbeen competed, when the optimization processing start button 305 ispressed, the application 300 optimizes the priority order number andlayout on the network of the respective terminal communication units120, causes to store the determined priority order number in thepriority order number storing unit 115 in the central communication unit110 via the host computer interface unit 140 and displays the determinedlayout of the terminal communication units 120 in the network on thenetwork connection configuration displaying portion 303.

Further, a communication cycle set by the communication cycle settingportion 311 in the communication performance setting portion 301 isstored in the communication cycle storing unit 116 in the centralcommunication unit 110 at the same time.

FIG. 4 shows in a form of flowchart a processing for optimizing thepriority order number set for the terminal communication units 120 andthe connection configuration on the network executed by the application300 after the optimization processing start button 305 is pressed.

At first, the application 300 calculates a transmission capacityoccupation rate of the network at the time of actual system operationbased on the communication cycle set in the communication performancesetting portion 301 (process 400).

Herein, when assuming that the communication speed of the network as V[bits/second], the data length (number of bits) when a communicationpacket is actually transferred as PLEN [bits], a number of packetsrequired for one time data communication of the respective terminalcommunication units 120 as PNUM_(x) (x=1, 2, . . . , n) [pieces], thetotal numbers of the respective terminal communication units 120 as nand the communication cycle set for the respective terminalcommunication units 120 as CYCLE_(x) (x=1, 2, . . . , n) [second], thetransmission capacity occupation rate U [%] is determined by calculatingthe following mathematical formula 1.

U=1/V×ΣPLEN×PNUM _(k)/CYCLE_(k) (k=1, 2, . . . , n)   [MathematicalFormula 1]

Subsequently, when the transmission capacity occupation rate determinedby the calculation in process 400 is larger than 100%, namely, when thesystem according to the set communication cycle exceeds the maximumperformance of the network (process 401), the application 300 displaysthe calculation result on the process display portion 304 as errorinformation (process 417).

When the transmission capacity occupation rate determined by thecalculation in process 400 is smaller than 100%, namely, when the systemaccording to the set communication cycle does not exceed the maximumperformance of the network (process 401), a plurality of terminalcommunication units having close values of communication delay time setat the communication performance setting portion 301 are grouped as onegroup, all of the terminal communication units are divided into samenumbers of groups as the numbers of the priority order number, theminimum values among the communication delay times in the respectivegroups are determined as the representative communication delay timesfor the respective groups and the priority order number is set for allof the terminal communication units so that the priority order becomessuccessively higher for groups having smaller representativecommunication delay time (process 402).

Subsequently, actual communication delay time that is communicationdelay time guaranteed by the actual system is calculated for all of theterminal communication units 120 according to the priority order numberset and the network connection configuration set at the networkconnection configuration setting portion 302 (process 403).

Herein, when assumed that a total number of terminal communication units120 contained in a group of a certain priority order number i (i=1, 2, .. . , m) as N_(i), priority order number set for the respective terminalunits as PRI (x) (x=1, 2, . . . , n), communication time required perone line of a communication cable 150 in the network as nDELAY [second],groups of terminal communication units 120 having priority order equalto or more than that of the concerned terminal communication unit 120 asHPG, a number of packets required for one time data communication of theterminal communication units 120 contained in HPG as PNUM_(y) {y|y ∈HPG}, the communication cycle of the terminal communication units 120contained in HPG as CYCLE_(y) [second], a coefficient of which initialvalue is 1 that is provided for every one of terminal communicationunits contained in HPG as A_(y), a maximum value of transmission waitingtime WAIT_(x) [second] of packets of the concerned terminalcommunication unit 120 that is required until transmission of packets tothe terminal communication units 120 having priority order equal to orhigher than that of the concerned terminal communication unit 120 hasbeen completed, is at first determined.

At first, the mathematical formula as shown in mathematical formula 2 iscalculated.

Subsequently, based on the calculation result according to themathematical formula 2, it is judged whether the mathematical formula asshown in mathematical formula 3 is fulfilled for all of y, every timewhen fulfilled, mathematical formula 4 is calculated, and aftercalculation, the value WAIT_(x)′ is replaced with WAIT_(x) and the valueAy′ replaced with Ay respectively.

After performing this calculation for all of y, again, the calculationaccording to mathematical formulas 3 and 4 is repeated. By repeating theabove calculation until mathematical formula 3 does not fulfill for allof y, a correct value of WAIT_(x) is determined.

Herein, when assumed the number of terminal communication units 120 tobe passed from the central communication unit 110 to the concernedterminal communication unit 120 as depth, and when the depth of therespective terminal communication units 120 is represented as DEPTH_(x)(x=1, 2, . . . , n), the actual communication delay time rDELAY_(x)[second] of the respective terminal communication units 120 of whichsetting in the input and output data updating mode setting portion 313is instant updating is determined by calculating the mathematicalformula as shown in mathematical formula 5 while making use of WAIT_(x)determined by the above calculation method.

WAIT_(x) =nDELAY×ΣPNUM _(y)   [Mathematical Formula 2]

WAIT_(x)/(A _(y)×CYCLE_(y))>1   [Mathematical Formula 3]

WAIT_(x)′=WAIT_(x)+(nDELAY×PNUM _(x)) A _(y) ′=A _(y)+1   [MathematicalFormula 4]

rDELAY_(x)=(nDELAY+1)×DEPTH_(x)+WAIT_(x)   [Mathematical Formula 5]

Further, an actual communication delay time cDELAY_(x) [second] of aterminal communication unit 120 of which updating is set in the inputand output data updating mode setting portion 313 as periodic isdetermined by calculating the mathematical formula as shown inmathematical formula 6.

cDELAY_(x) =rDELAY_(x)×2   [Mathematical Formula 6]

Subsequently, a comparison between the set communication delay time andthe actual communication delay time determined by the calculation isexecuted for all of the terminal communication units 120 (process 404)

As the result of process 404, when the actual communication delay timesof all of the terminal communication units 120 are smaller than the setcommunication delay times, namely, the set values of communication delaytime for all of the terminal communication units 120 are fulfilled(process 405), the application 300 causes to store the priority ordernumbers at this time as effective values in the priority order numberstoring unit 115 in the central communication unit 110, and to displaythe network connection configuration at this time as effective on thenetwork connection configuration setting displaying portion 303 (process416).

As the result of process 404, when an actual communication delay time islarger than the set communication delay time, namely, the set value ofcommunication delay time for at least one terminal communication units120 is not fulfilled (process 405), the setting of priority ordernumbers for all of the terminal communication units at this time isstored as a setting of incorrect priority order numbers in a memory ofthe host computer 100 (process 406).

Subsequently, when modifying the setting of the priority order number bymoving some of the terminal communication units 120 contained in a groupin another group, when there is at least one pattern that is not storedin the memory as incorrect priority order number setting among aplurality of priority order number setting patterns, namely, when thereis a priority order number setting pattern of which actual communicationdelay time is not yet calculated (process 407), the group of terminalcommunication units 120 is modifies so as to form one of priority ordernumber setting patterns other than the incorrect priority order setting(process 408), and the process returns to process 403 to perform thecalculation again.

Further, when modifying the setting of the priority order number bymoving some of the terminal communication units 120 contained in a groupin another group, and when all of the plurality of priority order numbersetting patterns are incorrect priority order number settings stored inthe memory, namely, when the actual communication delay time calculatedfor all of the priority order number setting patterns do not fulfill theset values of the communication delay time (process 407), if there is apossibility of fulfilling the set values of the communication delay timeby modifying the network connection configuration (depth) of theterminal communication units 120 (process 409), the priority ordernumber at that time is set for all of the terminal communication units120 (process 410).

Subsequently, the connection configuration of any terminal communicationunits 120 that do not fulfill the set values of the communication delaytime as above is modified so that the depth thereof on the networkbecomes small (process 411).

Subsequently, the actual communication delay time for all of theterminal communication units 120 is calculated according to the setpriority order number and the network connection configuration modifiedthrough process 411 in a like processing as process 403 (process 412).

As the result of process 412, when the actual communication delay timesof all of the terminal communication units 120 are smaller than the setcommunication delay times, namely, when the set values of communicationdelay time for all of the terminal communication units 120 are fulfilled(process 413), the application 300 causes to store the priority ordernumbers at this time as effective values in the priority order numberstoring unit 115 in the central communication unit 110, and to displaythe network connection configuration at this time as effective on thenetwork connection configuration setting displaying portion 303 (process416).

As the result of process 412, when an actual communication delay time islarger than the set communication delay time, namely, when the set valueof communication delay time for at least one terminal communicationunits 120 is not fulfilled (process 413), the network connectionconfiguration for all of the terminal communication units 120 at thistime is stored as an incorrect connection configuration in a memory ofthe host computer 100 (process 414).

Subsequently, when the layout of any terminal communication units 120that do not fulfill the set values of the communication delay time ismodified so that the depth thereof on the network becomes small, all ofnetwork connection configuration patters are taken out, and when thereis at least one pattern that is not stored in the memory as incorrectconnection configuration, namely, there is any room for improving theactual communication time by modifying the connection configuration(process 415), the connection configuration of the respective terminalcommunication units 120 is modifies so as to form one of the networkconnection configuration patterns other than the incorrect connectionconfiguration (process 411), and the calculation is performed again.

Further, when the layout of any terminal communication units 120 that donot fulfill the set values of the communication delay time is modifiedso that the depth thereof on the network becomes small, all of networkconnection configuration patters are taken out, and when all of thepatterns are the incorrect connection configuration stored in thememory, namely, when there is no room for improving the actualcommunication time by modifying the connection configuration (process415), if there is a possible priority order number setting method offulfilling the set values of the communication delay time by modifyingthe network connection configuration (depth) of the terminalcommunication units 120 (process 409), the priority order number is setfor all of the terminal communication units 120 (process 410), and thecalculation is performed again.

Herein, if there is no possible priority order number setting method offulfilling the set values of the communication delay time by modifyingthe network connection configuration (depth) of the terminalcommunication units 120 (process 409), the application 300 causes todisplay a combination of a communication delay time and a networkconnection configuration when the number of terminal communication units120 that do not fulfill the set value of the communication delay time isleast among combinations of the incorrect priority order number settingsand the incorrect connection configurations stored in the memory as anerror information.

Through the above processings, the software 101 in the host computer 100optimizes and determines the priority order number set for the terminalcommunication units 120 and the connection configuration (depth) on thenetwork of the terminal communication units 120 that can guaranteeoperations of a plurality of devices of control objects on one networkwith varieties of communication cycles and communication delay times.

FIG. 5 shows a method of storing the optimized priority order number forthe respective terminal communication units 120 through the processingby the application 300 and the communication cycle to the devicesconnected to the respective terminal communication units 120 set at thecommunication performance setting portion in the application 300respectively in the priority order number storing units 115 and thecommunication cycle information storing unit 116 in the centralcommunication unit 110.

The software 101 causes to store both the priority order number and thecommunication cycle in the priority order number storing units 115 andin the communication cycle information storing unit 116 whilecorrelating to the identification number assigned to the respectiveterminal communication units 120.

Further, the software 101 causes to store the input and output dataupdating mode set at the input and output data updating mode settingportion 313 in the application 300 in an instant communicationinformation storing portion 500 in the communication cycle informationstoring unit 116 in such a manner that when periodic as “0” and wheninstant as “1”.

FIG. 6 shows an example of displaying a result of the optimizationprocessing by the application 300. During when the optimizationprocessing is being executed after the optimization processing startbutton 305 is pressed, the application 300 causes to display theadvancing state of the processing on the process displaying portion 304,and to display success or fail of the optimization at the time ofcompleting the optimization processing.

Further, when the optimization processing is successful, the application300 causes to display the optimized network connection configuration onthe network connection configuration displaying portion 303, and whenthe optimization processing failed, the application 300 determines acombination having the least numbers of terminal communication units 120that do not fulfill the set value of the communication delay time in thecommunication performance setting portion 301 among combinations of theincorrect priority order number settings and the incorrect connectionconfigurations tried calculation during the optimization processing aserror information, and causes to display an error part indicating means600 at a part where the set value of the communication performancesetting portion 301 is not fulfilled, further, causes to display thenetwork connection configuration at this time on the network connectionconfiguration displaying portion 303, and to indicate an error partindicating means 601 on the terminal communication units symbols 321that cannot fulfill the set values in the network connectionconfiguration setting portion 302 and the network connectionconfiguration displaying portion 303.

Further, when a system user selects a terminal communication unit symbol321 designated by the error part indicating means 601, an errorinformation indicating means 602 is displayed indicating thecommunication cycle and the set value of the communication delay time inthe communication performance setting portion 301, and the actualcommunication delay time determined by the optimization processingcorresponding to the selected terminal communication unit symbol 321.

According to the present embodiment, a plurality of devices of controlobjects having different communication cycle and response performance onone network can be controlled with proper communication speeds. Further,since a proper setting of priority order of data communication with thecontrol objects and of layout of the devices of control objects on thenetwork, which is necessary for connecting a plurality of devices ofcontrol objects having different communication cycle and responseperformance on one network and for controlling with a propercommunication speed, can be optimized and determined through a softwareprocessing of the host computer, thereby, a network guaranteeing arequired performance of the respective devices of control objects can beeasily constructed.

Accordingly, an application field of the present invention to industrialmachines is generally broad, for example, although a chip mounter isconstituted by many control devices, and the communication cycles andresponse speeds required by the respective control devices arefrequently different, however, when the present system is appliedthereto, a network that fulfills the required performances of therespective control devices can be easily constructed.

EXPLANATION OF REFERENCE NUMERALS

100 Host computer

101 Software

102 Display unit

103 Information input unit

110 Central communication unit

111 Central communication control unit

112 Output data storing unit

113 a First data storing unit

113 b Second data storing unit

114 Identification number storing unit

115 Priority order number storing unit

116 Communication cycle information storing unit

117 Fifo type storing unit

120 Terminal communication unit

121 Terminal communication control unit

130 Communication port

131 Upstream communication port

132 a, 132 b Downstream communication port

140 Host computer interface unit

141 I/O port

150 Communication cable

200 Data portion

201 Packet type portion

202 Identification number portion

203 Priority order number portion

300 Application

301 Communication performance setting portion

302 Network connection configuration setting portion

303 Network connection configuration displaying portion

304 Process displaying portion

305 Optimization processing start button

310 Identification number setting portion

311 Communication cycle setting portion

312 Communication delay time setting portion

313 Input and output data updating mode setting portion

320 Central communication unit symbol

321 Terminal communication unit symbol

322 Connection state symbol

323 Communication port symbol

324 Upstream communication port symbol

325 a, 325 b Downstream communication port symbol

500 Instant communication information storing portion

600, 601 Error part indicating means

602 Error information indicating means

1. An industrial network system comprising: a host computer including adisplay unit, an information input unit and a software; an centralcommunication unit including a host computer interface unit, a first I/Odata storing unit, a second I/O data storing unit, an identificationnumber storing unit, a communication cycle data storing unit, at leastone communication port, at least two fifo type storing units per onecommunication port and a central communication control unit; and aplurality of terminal communication units each including one upstreamcommunication port, at least two downstream communication ports, atleast two fifo type storing units per one downstream communication port,at least one I/O port, a terminal communication control unit, anidentification number storing unit, a priority order number storing unitand a communication cycle information storing unit, characterized inthat the upstream communication ports of the terminal communicationunits are connected to the communication port in the centralcommunication unit or to a downstream communication port of any otherterminal communication unit in the plurality of terminal communicationunits.
 2. An industrial network system according to claim 1characterized, in that the central communication unit sends numbersrepresenting priority orders of data communication from the hostcomputer stored in the priority order number storing unit, the concernedterminal communication unit stores the received priority order number inthe priority order number storing unit, when sending output data to theterminal communication unit, the central communication unit cause tostore the output data in the fifo type storing unit corresponding to thepriority order number of the concerned terminal communication unit, thecommunication port takes out orderly output data from the fifo typestoring units according to the height of priority order and sends thesame, the terminal communication unit forms its own input data packet bycombining the input value from the I/O port and the priority ordernumber information stored in the priority order number storing unit andoutputs the same to the upstream, the data from the downstream arestored in separate fifo type storing units corresponding to the priorityorder number of the input data packet, and the input data packets storedin the fifo type storing units are orderly sent out according to theirheight of the priority order to the upstream communication port.
 3. Anindustrial network system according to claim 1 characterized, in thatthe central communication unit sends to terminal communication unitsindividual values of communication cycles required for every controlobject that is stored in the communication cycle information storingunit from the host computer, the terminal communication unit stores thereceived individual value based on the communication cycle in thecommunication cycle information storing unit and transfers the outputdata at a cycle based on the value to the respective terminalcommunication unit, the central communication unit causes to store theinput value of the I/O port received from the terminal communicationunit in a first input data storing unit, and cause to store the value inthe first input data storing unit in a second input data storing unitbased on the communication cycle in the communication cycle informationstoring unit, and the host computer confirms the values of the I/O portsof the respective terminal communication units with reference to thesecond input data storing unit in the central communication unit.
 4. Anindustrial network system according to claim 1 characterized, in thatthe summed value of the values of communication cycles stored in thecommunication cycle information storing units in all of the terminalcommunication units connected to the network is set below the maximumperformance of the network.
 5. An industrial network system according toclaim 4 characterized, in that in order to maintain the communicationcycles required for the respective control objects, the values of thepriority order number is set so that the time variability of thecommunication cycles of the terminal communication units is confinedwithin a range of one cycle.
 6. An industrial network system accordingto claim 1 characterized, in that the set values of the priority ordernumbers of the terminal communication units and number of terminalcommunication units to be passed from the central communication unit toan objective terminal communication unit are set based on acommunication delay time from a control object to the host computerrequired for the respective control devices.
 7. An industrial networksystem according to claim 1 characterized, in that the host computerdetermines communication delay times from terminal communication unitsfor the respective control objects by making use of priority of terminalcommunication units, number of communication packets of terminalcommunication units of which priority is equal to or higher than thepriority order set for the concerned terminal communication unit,communication time per one communication path and the number of terminalcommunication units to be passed from the central communication unit toan objective terminal communication unit, changes the priority of therespective terminal communication units so as to fulfill a communicationdelay time required for the control object and sets the priority of theterminal communication unit.
 8. An industrial network system accordingto claim 1 characterized, in that the host computer determinescommunication delay times from terminal communication units for therespective control objects by making use of priority of terminalcommunication units, number of communication packets of terminalcommunication units of which priority is equal to or higher than thepriority order set for the concerned terminal communication unit,communication time per one communication path and the number of terminalcommunication units to be passed from the central communication unit toan objective terminal communication unit, changes the layout of thecontrol object so as to fulfill a communication delay time required forthe control object and sets the number of terminal communication unitsto be passed from the central communication unit to an objectiveterminal communication unit.
 9. An industrial network system accordingto claim characterized, in that the software in the host computer isprovided with a function capable of setting the communication cyclerequired for the control object from the information input unit.
 10. Anindustrial network system according to claim 1 characterized, in thatthe software in the host computer is provided with a function capable ofsetting the communication cycles required for all of the controlobjects, a maximum allowable communication delay time and a connectionconfiguration (depth) of the terminal communication units on the networkfrom the information input unit.
 11. An industrial network systemaccording to claim 10 characterized, in that the setting function andthe display function of the network constitution included in thesoftware of the host computer are mounted through a GUI (graphical userinterface).
 12. An industrial network system according to claim 1characterized, in that a plurality of control devices constituting achip mounter are connected to the plurality of terminal communicationunits.